Shrimp Salad BLTs with Homemade Tarragon Mayonnaise

Name: Shrimp Salad BLTs with Homemade Tarragon Mayonnaise
Ingredients: 1 large egg yolk; 1 tablespoon lemon juice; 1/2 teaspoon Dijon mustard; Kosher salt; 1 cup grapeseed or vegetable oil; 1 1/2 tablespoons finely chopped fresh tarragon; 1 lemon, halved; 1 pound peeled and deveined shrimp; 2 celery ribs, halved lengthwise and thinly sliced; Freshly ground black pepper; 4 crisp cooked slices bacon; 2 medium heirloom tomatoes, sliced; 4 split-top hot dog buns, lightly warmed in the oven or toaster; 1 cup baby arugula